| Quiroz Construction | Garcia Quiroz Dagoberto | — | (408) 449 6476 | GC, remodel, ADU | Union City · Alameda County | — | — |
| Quixotic Construction | Kevin Hiroshi Ota | — | (510) 914 9758 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| R & A Plumbing | R & A Plumbing | — | (415) 572 3725 | Other | Dublin · Alameda County | — | — |
| R & B Equipment INC | Richard Werner Jeffery | — | (510) 782 3774 | Other | Hayward · Alameda County | — | — |
| R & D Builders INC | Kang Hyuk Lee | — | (510) 895 3894 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| R & G Framing INC | Roacho Gonzalo Rios | — | (714) 277 5129 | Other | Hayward · Alameda County | — | — |
| R & L Electrical Contractors INC | Roy Eugene Rud | — | (925) 570 9948 | Electricians | Pleasanton · Alameda County | — | — |
| R & L Mechanical INC | Bobbie Iii Knowles | — | (415) 651 4977 | HVAC | San Lorenzo · Alameda County | — | — |
| R & M Quality Windows And Doors | Michael James Easter | — | (510) 714 3617 | GC, remodel, ADU | Newark · Alameda County | — | — |
| R & R Construction | Mauricio Reynoso Rodriguez | — | (510) 589 5750 | GC, remodel, ADU | Union City · Alameda County | — | — |
| R & R Construction | Robson Nigel | — | (510) 384 9945 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| R & R French Bros DBA French Bros Flooring America | James Raymond Jr Levesque | — | (510) 444 5244 | Other | Oakland · Alameda County | — | — |
| R & R Insulated Glass Products | Ery Hernandez-Guzman | — | (650) 780 9163 | Windows, patio, painters | Fremont · Alameda County | — | — |
| R & S Appliance Installation INC | Robert Gabriel Santos | — | (925) 724 9455 | Other | Livermore · Alameda County | — | — |
| R & S Erection Incorporated | Johanna Varela Smith | — | (510) 483 3710 | Other | San Leandro · Alameda County | — | — |
| R & S Erection Of Southern Alameda County INC | Jerry Trask | — | (510) 489 6881 | Other | Hayward · Alameda County | — | — |
| R & S Landscaping & Maintenance | Terence Grant Johnston | — | (925) 846 6821 | Windows, patio, painters | Pleasanton · Alameda County | — | — |
| R & S Marble & Granite INC | Angel Daniel Rodriguez | — | (925) 667 4833 | Other | Livermore · Alameda County | — | — |
| R & S Overhead Garage Door INC | William Patrick Lawrence | — | (510) 483 9700 | Other | San Leandro · Alameda County | — | — |
| R A Custom Siding | Romel Alvarado-Flores | — | (510) 967 1012 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| R B A Cabinets | R B A Cabinets | — | (510) 415 2152 | Other | Hayward · Alameda County | — | — |
| R B Construction INC | Christopher Lee Luengo | — | (510) 683 8780 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| R C -d Concrete INC | Carlos Alberto Jr Pintos | — | (510) 477 8800 | Other | Union City · Alameda County | — | — |
| R C Flooring INC | Roberto Carlos Diaz | — | (510) 468 3038 | Other | Newark · Alameda County | — | — |
| R C Green Construction | Qiong Wang | — | (925) 381 3979 | Electricians | Dublin · Alameda County | — | — |
| R C Group | Fakurnejad Reza | — | (925) 788 4028 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| R C Gutter Services | Ramiro Cornejo | — | (510) 331 4425 | Other | Hayward · Alameda County | — | — |
| R C Plumbing | R C Plumbing | randy@rcplumbing.com | (510) 710 0404 | Other | Alameda · Alameda County | — | — |
| R C R INC | Ramon Perez Perez | — | (510) 538 1143 | Other roofers | Hayward · Alameda County | — | — |
| R C's Mechanical Services | Cortez Ruben | — | (510) 438 8806 | HVAC | Fremont · Alameda County | — | — |
| R Construction | Oswaldo Ramon Rivera | — | (925) 695 4482 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| R Custom Kitchen & Bath | R Custom Kitchen & Bath | — | (510) 384 9801 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| R D Electrical | Diaz Raymond | — | (510) 861 4345 | Electricians | Hayward · Alameda County | — | — |
| R D K Painting | R D K Painting | — | (510) 612 7633 | Windows, patio, painters | Newark · Alameda County | — | — |
| R D Renewable Energy Solutions | R D Renewable Energy Solutions | — | (925) 321 5375 | Electricians | Pleasanton · Alameda County | — | — |
| R Drywall Company INC | Rodriguez Ricardo | — | (510) 377 7932 | Other | San Lorenzo · Alameda County | — | — |
| R E Timm Construction INC | Raymond Ernest Timm | — | (925) 829 3436 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| R F Contractors | Mario Wagner | — | (510) 394 3300 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| R G E Construction | Robert Geoffery Engle | — | (510) 390 6134 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| R G Roofing | Ricardo Maldonado Garcia | — | (650) 759 0614 | Other roofers | Newark · Alameda County | — | — |